Fiber reinforced composite laminate with a thermoplastic urethane elastomer film

ABSTRACT

A fiber reinforced composite prepreg includes a prepreg containing reinforcing fiber and an uncured matrix resin, and a thermoplastic urethane elastomer film laid on the prepreg. A fiber reinforced composite laminate is formed by subjecting the fiber reinforced composite prepreg to hot pressing techniques. The thermoplastic urethane elastomer film enhances the bonding strength between the laminate and other materials bonded thereto.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to a fiber reinforced composite laminate, more particularly to a fiber reinforced composite laminate with a thermoplastic urethane elastomer film.

[0003] 2. Description of the Related Art

[0004] Fiber reinforced composite materials are characterized in their excellent mechanical strength, and can be used in many applications, such as shoes, skates, golf club shafts, tennis rackets, fishing rods, and the like. Conventional fiber reinforced composite materials are prepared using a prepreg as an intermediate material that contains reinforcing fiber and an uncured matrix epoxy resin. Epoxy resin exhibits a relatively weak bonding strength when bonded to other material, such as rubber, nylon, and polyurethane, using an adhesive or by injection molding techniques. As a consequence, the epoxy resin-based composite materials tend to separate from other materials bonded thereto after a period of use.

SUMMARY OF THE INVENTION

[0005] The object of the present invention is to provide a fiber reinforced composite prepreg with a thermoplastic urethane elastomer film that is capable of overcoming the aforesaid drawback of the prior art.

[0006] According to the present invention, a fiber reinforced composite prepreg comprises: a prepreg containing reinforcing fiber and an uncured matrix resin; and a thermoplastic urethane elastomer film laid on the prepreg.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In drawings which illustrate an embodiment of the invention,

[0008]FIG. 1 is an exploded perspective view of a preferred embodiment of a fiber reinforced composite prepreg according to this invention;

[0009]FIG. 2 is a schematic cutaway view of a shoe sole with a bottom layer made from the fiber reinforced composite prepreg of FIG. 1 and a top layer made from a rubber material;

[0010]FIG. 3 is a partly fragmentary sectional view of the shoe sole of FIG. 2;

[0011]FIG. 4 is a perspective view of a sports shoe sole made from the fiber reinforced composite prepreg of FIG. 1, with a plurality of studs made from other materials;

[0012]FIG. 5 is a sectional view taken along line V-V in FIG. 4; and

[0013]FIG. 6 is a schematic fragmentary sectional view of a golf club bag having a bottom made from the fiber reinforced composite prepreg of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0014]FIG. 1 illustrates a preferred embodiment of a fiber reinforced composite prepreg according to the present invention.

[0015] The fiber reinforced composite prepreg includes: a prepreg 10 containing reinforcing fiber 11 and an uncured matrix resin 12 and having opposite first and second surfaces 13, 14; and a pair of thermoplastic urethane elastomer films 15 respectively laid on the first and second surfaces 13, 14 of the prepreg 10. The fiber reinforced composite prepreg 10 is formed by impregnating the reinforcing fiber 11 in a solution of a resin composition.

[0016] The uncured matrix resin 12 is cured and is bonded to the thermoplastic urethane elastomer films 15 to form a fiber reinforced composite laminate by subjecting the prepreg 10 and the films 15 to a hot pressing process. Preferably, the uncured matrix resin 12 is made from an epoxy resin composition.

[0017]FIGS. 2 and 3 illustrate a shoe sole 2 including a top layer 22 of a rubber material and a bottom layer 21 of the fiber reinforced composite laminate made from the fiber reinforced composite prepreg 10. The shoe sole 2 is formed by placing a preformed structure of the fiber reinforced composite laminate in a mold (not shown), followed by injection of a hot melt rubber material into the mold to form the top layer 22. The thermoplastic urethane elastomer films 15 of the fiber reinforced composite laminate melt upon injection of the hot melt rubber material into the mold, thereby intermingling with the hot melt rubber material, which results in a strong bonding between the top layer 22 and the bottom layer 21 of the shoe sole 2.

[0018] Instead of using injection molding techniques, the top layer 22 can be bonded to the bottom layer 21 using an adhesive (not shown). Since the adhesive and the thermoplastic urethane elastomer are compatible materials, the bonding strength therebetween can be enhanced.

[0019]FIGS. 4 and 5 illustrate a sports shoe sole 3 with a plurality of studs 32. The shoe sole 3 is made from the fiber reinforced composite laminate of this invention. The studs 32 are made from polyurethane. Each of the studs 32 is formed with an inner thread 33 that is adapted to engage threadedly with a spike (not shown). Experimental results show that each of the studs 32 can sustain a pulling force of about 80 to 130 kg without separating from the shoe sole 3. However, without the thermoplastic urethane elastomer film, the studs can only sustain a pulling force of less than 20 kg.

[0020]FIG. 6 illustrates a golf club bag 4 with a bottom made from the fiber reinforced composite laminate of this invention.

[0021] By virtue of the thermoplastic urethane elastomer film 15, the bonding strength between the fiber reinforced composite laminate of this invention and other materials can be enhanced.

[0022] With the invention thus explained, it is apparent that various modifications and variations can be made without departing from the spirit of the present invention. It is therefore intended that the invention be limited only as recited in the appended claims. 

I claim:
 1. A fiber reinforced composite prepreg comprising: a prepreg containing reinforcing fiber and an uncured matrix resin; and a thermoplastic urethane elastomer film laid on said prepreg.
 2. The fiber reinforced composite prepreg of claim 1, wherein said uncured matrix resin is made from an epoxy resin composition.
 3. A fiber reinforced composite laminate comprising: a laminate that is formed by hot pressing a prepreg together with a thermoplastic urethane elastomer film, said prepreg containing reinforcing fiber and an uncured matrix resin, said matrix resin being cured and being bonded to said thermoplastic urethane elastomer film during the hot pressing.
 4. The fiber reinforced composite laminate of claim 3, wherein said uncured matrix resin is made from an epoxy resin composition. 